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2 years ago

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A rubber ball weighs 49 N.. a) What is the mass of the ball? (Answer: 5.0 kg). b) What is the acceleration of the ball if an upw

ard force of 69 N is applied? (Answer: 4.0 m/s/s). For a) I used the equation W = Fg = mg, which becomes 49 = m(9.8). This approximates m to 5.0 kg.
---
For b) I used the equation
ΣFy=Fa−W=ma
which becomes 69-49 = 20 N.
I then use equation F = ma which becomes 20 = 5.0a, which makes a
4.0m/s2

1 answer:

weqwewe [10]2 years ago

4 0

The answer you presented is correct.

For a) I used the equation W = Fg = mg, which becomes 49 = m(9.8). This approximates m to 5.0 kg.
<span>For b) I used the equation
</span><span>ΣFy=Fa−W=ma</span> which becomes 69-49 = 20 N.
I then use equation F = ma which becomes 20 = 5.0a, which makes a <span>4.0m/<span>s2</span></span>

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